A Study on Vision Ergonomic Assessment of LED Changeable Message Signs on Different Environment Illuminance

• Main Authors: Wen-Che Chung, 鍾文哲
• Other Authors: Chih-Fu Wu
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/84625300531432183621

碩士 === 大同大學 === 工業設計學系(所) === 99 === The light emitting diode (LED) has been gradually applied in the traffic engineering, but as to the LED changeable message sign (CMS) for engineering truck, only the outputs at different luminance (lx) are specified and the luminance is also standardized only to 85 lx. Since each country is in short of uniform specification currently, the research mainly discusses variable warning signs for engineering truck under different conditions and influences to provide references for the follow-up researches or for stipulating standards. In this research, three independent variables are set, and they are environmental illuminations of 50000 lx, 3000 lx and 10 lx, the background luminance contrasts consisting of 6200/0 cd/m2, 6200/3100 cd/m2, 6200/2066 cd/m2 and 3100/1033 cd/m2 and marking arrows in the forms of ”<<<”and ”←”. Based on those above, it discusses the remote and nearby legibility on the variable message signs. And the testees are asked to fill in their subjective and objective assessments so as to know the comfort and glare distance to the driver vision under the influence of various conditions. According to the research results, the lower the luminance contrast of warning sign is, the glare degree felt by the testees is higher. When the sign luminance contrast is 6200/2066 cd/m2, the maximum comfort and furthest glare distance can be got, which can help drawing the driver’s alertness earlier. As for the arrows, the glare distance of arrow “<<<” will be larger than that of arrow “←”, and the major reason is that the luminescent lamps of arrow “<<<” is much more than that of arrow “←”. When the environmental illumination is less than 5000 lx, the comfort distance and glare distance of “←” are further than those of arrow “<<<”. The research results can be supplied as references for other researches and for stipulating the standards.